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A325377 a(n) = A001065(A228058(n)), where A001065(n) gives the sum of proper divisors of n.

%I A325377 #8 Apr 22 2019 18:07:20
%S A325377 33,65,81,97,129,109,161,177,321,133,225,257,193,161,305,205,369,193,
%T A325377 253,401,417,253,449,465,277,641,561,349,609,801,641,289,397,397,705,
%U A325377 289,737,785,801,481,353,469,385,337,929,945,977,2241,565,1041,1281,1089,613,1121,637,1137,481,1185,673,685,1265,709,1281,421,2717,545,1601
%N A325377 a(n) = A001065(A228058(n)), where A001065(n) gives the sum of proper divisors of n.
%H A325377 Antti Karttunen, <a href="/A325377/b325377.txt">Table of n, a(n) for n = 1..25000</a>
%F A325377 a(n) = A001065(A228058(n)).
%F A325377 a(n) > A325320(n) for all n.
%o A325377 (PARI)
%o A325377 up_to = 25000;
%o A325377 isA228058(n) = if(!(n%2)||(omega(n)<2),0,my(f=factor(n),y=0); for(i=1,#f~,if(1==(f[i,2]%4), if((1==y)||(1!=(f[i,1]%4)),return(0),y=1), if(f[i,2]%2, return(0)))); (y));
%o A325377 A228058list(up_to) = { my(v=vector(up_to), k=0, n=0); while(k<up_to, n++; if(isA228058(n), k++; v[k] = n)); (v); };
%o A325377 v228058 = A228058list(up_to);
%o A325377 A228058(n) = v228058[n];
%o A325377 A001065(n) = (sigma(n)-n);
%o A325377 A325377(n) = A001065(A228058(n));
%Y A325377 Cf. A001065, A228058, A325320, A325380.
%K A325377 nonn
%O A325377 1,1
%A A325377 _Antti Karttunen_, Apr 22 2019